PLANTATION RUBBER INDUSl^RY OF THE EAST. 497 



On the question of tapping, Parkin investigated the yield 

 from single incisions in varying directions, and from V cnts, 

 and concluded that, unless the flow was poor, the V did not 

 give double the yield of the single oblique cut. He tapped 

 with chisels of various patterns, and collected the latex in 

 tins provided with a spike to fix them to the tree, and a lid to 

 prevent bark, &c., falhng in. Throughout he employed the 

 single cuts recommended by Cross and Wickham, and did not 

 experiment with the herring-bone method or the timber 

 scoring*knife recommended by Collins. His notes on " wound 

 re-action," now generally known as " wound response," 

 constitute the first attempt at an investigation into that 

 phenomenon, though in the actual observation of it he was 

 ante-dated, so far as the East is concerned, by Curtis ; Willis 

 had recorded in the previous year that the second tapping 

 yielded more than the first, without making any special 

 comment on its importance. Parkin advised that the tree 

 should not be tapped all round, though he only contemplated 

 single incisions. His results on tapping are of fundamental 

 importance, though he did not attempt the method of re- 

 opening the cut now universally adopted. His remarks on 

 that point appear to show that he was acquainted with that 

 method, but rejected it as too dangerous : Curtis visited 

 Ceylon in 1899, and described the method, but too late for 

 it to be employed in Parkin's experiments. 



It may be noted that the dates given in Parkm's Circular 

 are conflicting : it is signed April 13, 1898, by Parkin, and 

 May 25, 1899, by Wilhs, while the date of publication is given 

 as June, 1899. The experiments described extend to June 6, 

 1899. 



In dealing with the latex. Parkin departed altogether from 

 the practice hitherto current. It had previously been the 

 custom, in all the recorded experiments, to allow the latex to 

 coagulate naturally in the collecting cups, and hence it was 

 considered necessary to tap only in the dry weather and to 

 prevent rain water entering the cups. Parkin, however, 

 realized the necessity of bulking the latex, and preventing 

 coagulation in the collecting cups : he therefore put water in 

 the cups, and advised that dilute ammonia should be used 



6(4)14' («4) 



